CHICAGO, JAN 21: The madcow trial pitting US talk show star Oprah Winfrey against Texas ranchers has put the spotlight on America's `food disparagement' or `veggie libel' laws.Jury selection in the high-profile trial began on Tuesday in the North Texas town of Amarillo, following a $ 12 million-lawsuit by local cattlemen against Winfrey, perhaps America's most popular television personality.The suit alleges that Winfrey and her production company libeled the beef industry during a 1996 show on mad cow disease, a brain-wasting ailment also known by the scientific name, Bovine Spongiform Encephalopathy (BSE.)Many scientists believe BSE is linked to a deadly equivalent neurological disease in humans, and Winfrey vowed on air to stop eating hamburgers, out of fear of contracting the fatal disorder.Shortly after the program was aired, consumption of beef declined in the US and Texas cattlemen suffered huge losses.Ranchers claimed that negative and they claimed incorrect information about US beef broadcast on Winfrey's program caused the drop in beef consumption.Their lawsuit also targets Howard Lyman, the vegetarian activist who asserted on Winfrey's show that the routine practice of feeding cattle protein additives containing meat and bonemeal carries the risk of spreading BSE as has happened in Britain and elsewhere in Europe. Texas ranchers claimed that Lyman's warnings about the possibility of BSE in US beef ``goes beyond all possible bounds of decency and is utterly intolerable in a civilised community''.Thirteen farming states that have passed veggie libel laws in the US since 1994, following intense lobbying by the food industry, after apple growers lost a lawsuit against the CBS television network over the health hazards of a pesticide.Such laws allow producers of perishable farm food products to sue for compensatory and punitive damages when false or disparaging information is spread about the safety of their products.But critics, including environmental activists and consumer advocates, say veggie libel laws chill free speech and stanch the flow of information in the food safety debate.The Texas law has come under particular criticism because unlike similar statutes in 12 other states, it places the burden of proof on the plaintiff.Other US states which have introduced veggie libel statutes are: Alabama, Arizona, Colorado, Florida, Georgia, Idaho, Louisiana, Mississippi, Ohio, Oklahoma, North Dakota and South Dakota.